#include <bits/stdc++.h>

using namespace std;

class Solution {
   public:
    int countSeniors(vector<string>& details) {
        int ret = 0;
        for (auto& s : details) {
            int age = atoi(s.substr(11, 2).c_str());
            if (age > 60)
                ret++;
        }
        return ret;
    }
};